Wireless Frequency Modulated (FM) radio transmissions are used for several purposes. For example, FM transmissions are used to allow and assist communication in cordless phones, walkie-talkies and baby monitors. One particular use is to use FM transmissions to assist the situation for people being hearing impaired. The equipment commonly comprises a transmitter, which captures a sound from the person speaking, and transmits the sound using an FM signal from the transmitter to a receiver carried by a user. The receiver is able to convert the FM signal to a sound, typically using some type of earpiece, allowing the user to hear the person speaking more clearly. This type of transmission system is crucial to allow the user to handle situations like lectures, meetings, television, radio and theatre.
One problem with the transmission systems in the prior art, is that transmissions may easily be received by non-intended users, preventing private meetings to be held securely. Moreover, because the signal is typically transmitted on a relatively low frequency, large and bulky antennas are required, leading to inconveniently large transmitters and, more importantly, large and bulky receivers.